Machine-gun and the like.



H. T. LOGAN( MACHINE GUN AND THE LlKE. APPLICATION msn JULY 20. 1911.

1,318,214. Patented oct. 7,1919.

.num'i'noxss or Immos, msnm.

nomia-GUN Lm.

i To'all whom it may concern Be it known that I, Hmmmr THOMAS LOGAN, a subject of the Kin of England, of 3 Ravencourt Square, ammersmith, London, `W., England, at present with the British Expeditionary Force, France, have invented certain new and useful Im rovements -in Machine-Guns and the e, of which the following is a specification.

This invention is for improvements in or relating to machine-guns and thelike, and has for its objectto provide means whereby the rate of automatic firing can be reduced or varied from the maximum downward to any desired extent while yet maintaining the automatic action.

The invention relates to machine-guns of the type having a member which is reciprocated automatically and effects the ignition of a cart-ridge when driven forward by asprin'g, or sets the parts ready for the release of the firing-bolt, thesaid spring vhaving been loaded bythe previous rearward movement ofthe reciprocating member. This member is variously termed Ithe r breech-block, firing-bolt, piston-rod, accord- Aals ing tothe type of gun in which it is found,

and i has a rectilinear movement, being Vdriven forward for firing or preparatory to firing by its spring and rearward to load the spring by the recoilresulting from the explosion of the charge. vIn the .303 Lewis machine-gun, this member is known as the piston-rod, and .this term will be used throughout this specification and claims for the reciprocating-member as the invention ploy a dashpot device for-slowinf will be Lewis gun, but it willbe understood that the term includes any similar reciprocating member in other makes of s and the invention is not restricted to t e Lewis gun.-

It has previously been proposed to emthe rate a s ringof rin and this device comprise back control ed member whichvwas pushe against its spring yby the return movement of the breech-block which takes place after one shot has been fired prior to the next being iired. After the set-back of the dashpot member for the Ybreech-block the final movement of the latter left the dashpot member free so that it could advance and' strike .the same for the next release for ring; the length of the riod between the return of the breech-bloc Bpedtion ot Letten Patent.

Application med July $0, 1917. Serial lo. 181,880.

escribed with reference to the saidrelease-valve.

and the next op-l eration for firingl thus depended upon 1 the degree of leakage allowed the dashpot mechanism. The hand-trigger or its equlvalent also controlled mechamsm for eff the operation of the scar automatically with- O out waiting for the movements of the dashpot member when full-speed firing -was required. The dashpot mechanismcould only be operated at one s eed unless an adjustingscrew controlling t e leakage was operated 05 to effect a re-adjustment of the rate of firb K ing, which screw was not accessible with'- out stoppmg the action of the gun.

Accordngfto the present invention, a

of the type described and hav- 'lo' machine-gian mg a das pot' mechanism for retardin the ring movement of the piston has (com ined y with the hand-trigger a release-valve for the dashpot and operative connecting means vention a machine-gun of the type described I having va dashpot device :for` retardin the rate of firing has combined with the piston- -rod means for automatically locking the latter back a inst forward movement for Abetween this and the trigger so that as the. 75'

ring when t e hand-trigger is still in the firing position and means operativel connecting the dashpot with the aforesai automatic locking means to release the same by the return movement of the dashpot.

Preferabl the operative connection be- 8e ainst the hand-trigger so that when the latter is moved to the firing position it releases the piston-rod and when the hand-trigger is still further moved back the sear is brought into contact with and commences to open the The accompanying drawing, which is en- 'tirely diagrammatic, illustrates thatpart of f a Lewis gun to which the present invention applies.

he' piston-rod A is normally locked baci: 105 .against its controllin 1 shpwn,but it operates to drivethisforward 110v t in the direction' indicated by the arrow and is loaded by the recoil movement of theV `for them in the piston-rod A.

v Mounted beneath the sears is a dashpot F in which slides a dashpot-member F1, the said member being in the form of a hollow piston driven outward by a spring F2. Behind the piston is a spring-controlled valve G of the needle type, which, when depressed against the 'action of its spring, admits air to the dashpot, andA a non-return Valve G1 is provided whereby air can be expelled from the dashpot. K v.

v The dashpot-member F1 has at its forward end a projection F3 which lies in the path 0f the tall-end D1 of the Sear D. A lever H is pivoted at H1 and has pivotal connection at H2 with the forward-end 'of the dashpotmember. At the upper end of the lever H, a well-known one-way trip devicel H3 is mounted, and cooperating with this is a catch A3 on the piston-rod A.

The operation of f this mechanism is as follows:-- t

When the trigger C is pulled back in the direction of the arrow for ring, the Sear B is first released and this, if no second sear l were provided, would start the gun firing at-full speed. Ai; the time of starting, the second sear is held back by the dashpot member so that one shot is fired directly the first sear C is released by the hand-trigger.

Cn the recoil of the piston-rod the second scar D drops into the notch Az'and remains there until the dashpot-member F2 has moved out on its return movement so that its forward end comes into contact with the tailend D1 of the sear, and thisvwithdraws the sear. The piston-rod then advances and fires the next cartridge. In this' advance, the catch A3 passes the lever H, which will be in the position indicated by dotted lines, by swinging over the trip, also indicated by dotted lines. The recoil then returns the piston-rod and in so doing the catch Asengages the end of the lever H and brings it.

back to the position shown in full lines so that the dashpotmember is thrust into the dashpot against the action of the spring 'F2 which is thereby loaded and the 'surplus air from the dashpot is expelled through the valve G1. The lever H in swinging over is brought out of the path of the catch A; so that the catch can pass on to the posiu tion shown in full lines, in which osltion the piston-rod is fully returned. irectly mman lthe returny has taken place, the dashpot opened at all, the mechanism will operate' at its slowest, as the advance of the dashpotmember F1,` can then only take place at the rate at which the dashpot can till' with air through leakage, but if the trigger C is' pulled back farther, the sear B 1s' brought down upon the top of the valveA G and dis? places it against the action of its spring. In the drawing, the sear is shown as resting upon the top of the valve but not yet depressing the same. therefore, that the farther the trigger C is pulled back, the greater will be the freedom with'which the dashpot is lilled with air and thusl its speed of operating will increase and so the rate ofl firing can be, increased.

It will be appreciated, v

To enable the firing to take place at full speed, the timing-device can be cut out en-v tirely. This is done by a depending lug D2 on the sear'D which carries a pin This pin projects laterally beneath the sear B so that when the trigger'C is ulled right back, the sear B will engage t is pin and hold the sear D free of the notch-A2 in the` piston-rod. t

From the above it will be seen that a large range of adjustability .is permitted so that the gun might be made to fire at any rate desired, say, 'from one shot in one or more minutes up to the full speed, but in some cases it lmight be preferredyto provide the gun with only two 'speeds,'that is, one 1n which the dashpot is operative with a given size of air-admission orifice and the other in which the dashpot is cut out so that the gun works at full-speed; such an arrangement it willbe understood is covered b the term .adjustable timing-device, a though the timing-device itself in such case is only operative at one speed andcut out for the other.

What I claim as m t'o secure by Letters invention and desire atent 1s l. In a machine gun, the combination with` spring, of means operatively connecting the ber, a4 regulating member for controlling the latter, and means adapted to be driven 'by the reooiling piston rod for driving the 'said driving member against the action of its trigger with said regulating member so that the timing device is controlled 'by movlng the trigger. e

' 2. In a machine gun, the combination with the piston rod and a dashpot device comprising a plunger, Yfor retarding the rate of firing, of locking means for automatically locking the piston rod back against forward movement for firing when the trigger is still in the firing position, the said plunger being adapted4 to release the said locking means durin its return movement.

3.' Ign a machine gun, the combination with the piston rod, and the trigger, of locking means operatively connected with thetrigger for automatically locking the piston rod inits rear position when the trigger is in its normal position and for releasing the same when the trigger is in its firing position, a valve-controlled timing device for retarding the rate of firing controlled by said locking means, and a lockingv device adapted to be actuated by said timing device for auto-` vmatically alternately locking the piston rod in its rear position and releasingVx the same for firing while the trigger is still in its iirin position.

4. n a .machine gun, the combination with the' piston rod and the tri ger, of a sear operativel connected Wlth t e trigger Vfor automatica y locking the piston rod in its rear position when the trigger is-in its normal position and for releasing 'the same when the trigger is in its rin position, a valve-controlled timingdeviceor retarding the .rate of firing controlled by said sear,

and a second Sear adapted to be actuated by said tim' device for automatically al- Iternatively lldlring the piston rod in its rear position and releasing the same for firing Y while the trigger is still i'n itsv firing position.

5. In a machine gun, the combination with the piston rod and the trigger, of a sear operatively connected with the trigger and adapted to be rocked thereby into an end locking position for locking the piston rod in its Vrear position when the. trigger is in its normal position, and into an, end

withdrawn position after releasing the piston rod when -the trigger is in its firing position, a valve-controlled timing device for retarding the rate 4of firing controlled by said s'ear, -and a second sear adapted to be actuated by said timing device afterthe re' lease of the iston rod bythe former Sear for automatica'l y'alterna-tely locking the piston rod in its rear position and releasin the same for liringwhile the trigger is still 1n its firing position the former scar being adapt'- -ing the same for firin ed to coact with'and arrest the second scar in its releasing position when the former sear is rocked into its end withdrawn position.

6. In a machine gun, the combination with the piston rod and the trigger, of a springiniluenced sear operatively connected with the 'trigger and adapted to be rocked there-v by into an end locking position for locking y the piston rod in its rear position whenthe trigger is in its normal position, and into an end Withdrawn position after. releasing the piston rod when 4the tril ger ish in its firing position,` a valve-contro ed timmgdevice for retarding the rate of ring controlled by said sear, land a second springin'iuenced sear havinga tail piece adapted to be actuated by said timing device after the release with the' iston rod by the former sear for automatica y alternatively locking the piston rod in its'rear position and releasw-hile/the trigger is still in itsI ring member. carried y the second "Sear and 'adapted to be held by the former sear and 'piston rod has been released and the trigger` has been moved into its firingy osition.

8. In a machine gun, the com' ination of a piston rod, a trigger, a spring-pressed sear having one end operatively connected to the trigger and its otherend normally locking the piston rod in its rear position, anadjustable timing device com rising a dashpot having anair-port, a valJve controlling the air port adapted 'to be operated by the Sear,

vso

positlon, and a proJecting od, and a ,sear hava spring-pressed plunger movable in the '.dashpot, a lever pivotally connected to the plunger and a trip device carried by the- -plunger and adapted to be driven by the piston rod during its recoil, and a second A spring pressed sear having one end normally locking the piston rod in its'rear. sition and havlng on its other end a tail-piece adapted to be actuated lby the plunger for releasing the piston rod. y

,In testimony whereof -I have signed my. name to this specification. Y

HUMPHRY THOMAS LOGAN. 

